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Altera_Forum's avatar
Altera_Forum
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11 years ago

Can i use Stratix iv gx CMU channels as transceiver ?

I checked all altera's devkit boards, they all didn't use this kind of channels as transceiver. They only were used as ref clock input. Our project has over used all normal transceiver channels, now we need to add a pcie-x4 interface in our system, and must release 4 used transceiver channels to implement pcie interface, and use 4 CMU channels to replace them. My question is that can we use the cmu channels as transceiver? Our speed is not very high, 2G is enough for us.

Also, someone told me that if we use that CMU channels we need design the PCS logic by ourselves. Because these CMU channels don't have PCS modules, they only have PMA compare with normal transceiver channels. Another question is how to design this PCS user logic?

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Hi,

    Stratix IV GX CMU channel can be used as transceiver. However, as you are told, it can only be used in PMA only mode with supported data rate 600Mbps - 6.5Gbps. You can refer to Stratix IV device handbook, volume 2 -> Configuring CMU Channels as Transceiver Channels section for further details.